Container for use in treatment of liquid

ABSTRACT

A container for use in batch treatment of a liquid, particularly blood, such as centrifugal separation of blood into fractions of different densities and/or for washing blood cells suspended in a liquid, comprises walls of flexible sheet material which define between them a closed compartment for holding a quantity of liquid and a conduit which communicates with the compartment. The conduit is adapted to be acted on by a peristaltic pump for moving liquid through the conduit to or from the compartment or alternatively the conduit prevent liquid flow through the conduit.

United States Patent Unger et al.

CONTAINER FOR USE IN TREATMENT OF LIQUID Inventors: Hans Peter OlofUnger,

Oregrundsgatan l, Lidingo; Eric J. H. Westberg, Rodstugevagen 14,Stockholm; Stephan L. Schwartz, Granitvagen l, Lidingo, all of SwedenFiled: Nov. 14, 1972 Appl, No.: 306,218

Related Us; Application Data Division of Ser. No. 233,538, March 10,1972, Pat. No. 3,724,747.

Foreign Application Priority Data Mar. 15, 1971 Sweden 3309/71 Mar. 15,1971- Sweden 3310/71 U.S. Cl. 233/27 Int. Cl B04b 7/12, B04b 15/06 Fieldof Search 233/20 R, 26, 27, 28, l R,

' A container for use in batch treatment of a liquid, par- Jan. 7, 1975[56] References Cited UNITED STATES PATENTS Primary Examiner-George H.Krizmanich Attorney, Agent, or FirmLarson, Taylor and Hinds ABSTRACTticularly blood, such as centrifugal separation of blood into fractionsof different densities and/or for washing blood cells suspended in aliquid, comprises walls of flexible sheet material'which define betweenthem a closed compartment for holding a quantity of liquid and a conduitwhich communicates with the compartment. The conduit is adapted to beacted on by a peristaltic pump for moving liquid through the conduit toor from the compartment or alternatively the conduit prevent liquid flowthrough the conduit.

6 Claims, 4 Drawing Figures PATENTED I 3,858,796

Illllll CONTAINER FOR USE IN TREATMENT OF LIQUID This application is adivision of my copending application Ser. No. 233.538, filed Mar. 10,1972, now US. Pat. No. 3,724,747.

This invention relates to a container for use in treatment of liquidparticularly for use in a centrifuge for treating discrete quantities ofa liquid by separating it into fractions of different densities and,where desired, by washing soild particles suspended in liquid. Theinvention has particular application to the centrifugal treatment ofblood and the present disclosure will be devoted primarily to thisapplication. It should be understood, however, that the invention isapplicable to the treatment of other liquids than blood. It should alsobe noted that the term liquid as used in this specification embraces notonly true liquids but also other materials resembling liquids such asthe semi-liquid mass of blood cells obtained from whole blood afterseparation of the plasma.

It is known to treat discrete quantities of blood in a closed system ofcollapsible containers in a centrifuge rotor. Thus, one container mayinitially hold a batch consisting of either a mixture of whole blood anda liquid preservative or a suspension of red blood cells in a liquidpreservative and a second container may initially hold a quantity of awash solution while a third container is initially empty. The containersare interconnected through conduits and during the treatment plasmaand/or preservative from the first container is passed into the emptythird container and temporarily replaced by wash solution from thesecond container. After agitation of the contents of the first containerthe used wash solution and the material washed off from the blood cellsis passed into the third container leaving the washed red cells in thefirst container.

The use of collapsible closed containers for the blood, for separatedfractions and for wash solution enables the treatment to be carried outunder sterile conditions since the containers can be interconnected in aclosed system to communicate with each other without their contentscoming into contact with the ambient atmosphere or exterior surfaces.The transfer of liquid between the containers has presented problems,however, since the transfer normally has to take place while thecentrifuge rotor and the container system rotate at high speed.

A general object of the present invention is to provide an improvedcontainer construction permitting the transfer of liquid to be effectedand controlled in a simple and reliable manner.

A more specific object in accordance with the foregoing general objectis to provide a container for use in a a centrifuge in which the rotorsupports a pump for displacing liquid to and from the container.

Another object is to provide a centrifuge which can be loaded with thecontainers and made ready for operation with a minimum of manual labor.

In one embodiment of the invention these and other objects are realizedin a container for use in a centrifuge in which the transfer of liquidis effected by a peristaltic pump. The container has three circularwalls of flexible sheet material which walls define between them twoclosed annular compartments for liquid. The walls in the centralportion, inwardly of the liquid compartments, also define between themconduits communicating at one end with the liquid compartments. Theconduits are adapted to cooperate with the peristaltic pump when liquidis to be transferred to or from the liquid compartments, the peristalticpump is caused to rotate slowly with respect to the container todisplace liquid through the conduits. When the peristaltic pump memberis stationary with respect to the the container, it compresses theconduits to block flow therethrough.

The above and other objects and features of the invention will becomeapparent from the following detailed description taken in conjunctionwith the accompanying diagrammatic drawings.

FIG. I is a view in vertical section ofthe rotor and associated parts ofa centrifuge provided with a container constructed in accordance withthe invention;

FIG. 2 is an enlarged view corresponding to the central portion of FIG.1;

FIG. 3 is an exploded partly cut away perspective view of the containerassembly in the centrifuge shown in FIGS. land 2;

FIG. 4 is a plan view of the central portion of the twocompartmentcontainer shown in the lower portion of FIG. 3.

The centrifuge diagrammatically illustrated in FIG. 1 has a framesupporting a centrifuge rotor 11 for rotation about a vertical axis athigh speed, e.g., 3,000

rpm, by means of a motor 12. Rotor lll includes a bowl 13 having adepending hollow journal member 14 mounted in a ball bearing 15 in frame10. The rotor bowl and most other elements of the rotor are circular inplan view.

Rotor bowl 13 houses a container assembly thedetails of which are bestseen in FIG. 3. It includes a lower two-compartment container 16supported on the bottom wall of bowl l3 and an upper single-compartmentcontainer 17 supported on top of container 16. Both containers aregenerally disk shaped and concentric with the rotorbowl. They are bothclosed, disregarding openings for the introduction and removal ofliquid, and made of a thin and flexible sheet material so as to becollapsible. The sheet material may be, for example, a laminate ofpolyethylene and polyester having a total thickness of about 0.1millimeter.

Lower container 16 is made of three circular sheets l8, 19, 20 disposedone on the other and sealingly joined along their peripheries by acontinuous heat seal 21 and at their central portion by another circularheat seal 22. Lower and central sheets 18, 19 define between them acompartment 23 which initially holds wash solution and central and uppersheets 19, 20 define between them a compartment 24 which is initiallyempty.

In the central portion of container 16, heat seals 25 (marked by closelyspaced dash lines in FIG. 4) joining sheets I8, 19 define a collapsibleconduit 26 through which wash solution in compartment 23 can flow to ashort connecting tube 27 secured to upper sheet 20 around an opening 28in the latter via an opening 311 in sheet 19 (see also FIG. 2). Similarheat seals 29 (marked by closely spaced full lines in FIG. 2) joiningsheets 19, 20 define another collapsible conduit 30 through which liquidcan flow from connecting tube 27 to compartment 24. Portions of conduits26, 30 extend along two concentric circles and cooperate with a pump 32described in more detail hereinafter. This pump is operable to producethe liquid flow and to block the conduits when flow is not desired. Heatseal 22 prevents liquid in the two compartments from entering thecentral container portion except through the conduits.

Upper container 17 initially holds a quantity of blood cells suspendedin a liquid preservative. It consists of two sheets 33, 34 which arejoined by a heat seal 35 at their peripheries and a heat seal 36 attheir central portions so that they define between them an annularcompartment. A connecting tube 37 communicates with this compartmentthrough a conduit 38 defined by heat seals. An opening 39 in the centralportion permits tube 37 to be connected with tube 37 of container 16.

Conduits 26 and 30 as well as conduit 38, owing to the characteristicsof the material and the manner in which they have been produced, have astrong natural tendency to close themselves. Thus, in order that theymay permit the liquid in the containers to pass through them, the liquidmust be subjected to a substantial pressure. Therefore, no specialprecautions are necessary to prevent unwanted flow through the conduitsduring manual handling of the containers.

Referring again to FIG. 1, a filler ring 40 and a backing plate 41 aredisposed between containers 16 and 17. Connecting tube 27 extendsthrough an opening in the backing plate and is connected to connectingtube 37.

Rotor 11 includes a cover assembly with a rigid cover plate 42 which hasan internally screw-threaded boss 43 and holds an annular body 44 madeof soft rubber mixed with lead granules so as to have higher specificgravity than the liquids in the containers. A clamping mechanism havingan externally screw-threaded sleeve 45 screwed into boss 43 and a numberof circumferentially distributed wedges 46 connected to the sleevethrough rods 47 cooperates with cover plate 42 and bowl 13 to hold downthe cover assembly against the containers. A photoelectric detector 48mounted in sleeve 45 signals the presence of red blood cells inconnecting tube 37.

Pump 32 referred to above is of the well-known peristaltic type whichhas a plurality of rollers moved in a circular path to progressivelycollapse a resilient conduit so as to displace liquid in the conduit. Ithas two concentric and independently movable circular groups of rollers,each comprising three rollers spaced apart 120. The outer group ofrollers 49 are rotatably mounted on an outer rotor member 50 secured toa hollow shaft 51 which is concentric with rotor 11. These rollerscooperate with conduit 26. The inner group of rollers 52 are rotatablymounted on an inner rotor member 53 secured to a shaft 54 extendingcoaxially through shaft 51. These rollers cooperate with conduit 30.

As best seen in FIG. 2, rollers 49 and 52 engage conduits 26 and 30through a flexible diaphragm 55 to lo-' cally compress and close theseconduits against backing plate 41.

Rotor members 50 and 53 normally are stationary with respect to therotating centrifuge rotor and the containers but when desired they canbe slowly rotated with respect to the centrifuge rotor during rotationof the latter. Positive rotational movement of rotor member 50 isderived from journal member 14 of rotor bowl 13 by means ofa gear 56engaging a gear on the journal member and another gear 57 engaging agear on hollow shaft 51. Gears 56 and 57 are mounted for rotation abouta common axis but normally there is no driving connection between them.However, a magnetic clutch 58 can be actuated to cause these gears torotate in unison so as to bring about slow rotation of rotor member 50with respect to container 16 (clockwise as seen from above in FIGS. 1, 2and in FIG. 4). Similarly, positive rotational movement of rotor member53 (anticlockwise) is derived from journal member 14 through gears 59,60 and a clutch 61.

The procedure for the treatment of the blood cells in container 17 willnow be described. Rotor 11 is assumed to be stationary but assembled asshown in FIG. 1, although compartment 24 of container 16 is empty sothat sheets 19 and 20 engage each other face to face under the influenceof pressure from rubber body 44. Thus, the peripheral portions of thecontainers are clamped between the bottom of bowl 13 and filler ring 40and between the latter and rubber body 44. The central portions of thecontainers are clamped between the rollers of pump 32 and the lower endof boss 43 of cover plate 42. The rubber body in conjunction with theshape of the parts ensure that unwanted air pockets adjacent thecontainers are virtually eliminated.

Rotor 11 is then caused to rotate with clutches 58, 61 disengaged sothat pump rotor members 50, 53 rotate in unison with the centrifugerotor owing to the friction between these rotor members and diaphragmand other parts of the centrifuge rotor. Under the influence of thecentrifugal forces, the heavy soft rubber of body 44 is forced outwardlyto apply an external pressure to containers 16, 17. Owing to thearrangement and shape of the parts, this pressure forces the liquid inthe containers inwardly and causes conduits 26, 30 to assume theexpanded form shown in FIG. 2. However, since the rollers of the rotormembers are stationary with respect to the rotor and the containers andcompress the conduits, no liquid is permitted to pass through thelatter.

The centrifugal field, which may be of the order of 1,000 g, causes theformation of fractions of different densities in container 17, that is,the red blood cells accumulate in the radially outer portion ofcontainer 17 while the lighter preservative liquid is collected in theradially inner portion. Clutch 61 is then engaged to cause inner rotormember 53 to rotate anticlockwise (FIG. 4) with respect to thecentrifuge rotor and the containers so that the preservative liquid ispumped from container 17 into compartment 24 of container 16 throughconduit 38, connecting tubes 37, 27 and conduit 30. Since outer rotormember 50 is still stationary with respect to the centrifuge rotor andthe containers, the preservative liquid is prevented from flowingthrough conduit 26.

When detector 48 signals the presence of red blood cells in tube 37,clutch 61 is again disengaged and clutch 58 engaged so that outer rotormember 50 is caused to rotate to pump wash solution from compartment 23into container 17 through conduit 26. tubes 27, 37 and conduit 38 whileinner rotor member 53 is held stationary to prevent flow through conduit30. When a sufficient amount of wash solution has been transferred,clutch 58 is disengaged so that both conduits 26, 30 are closedwhereupon rotor 11 is rapidly braked (by means not shown) to low speedto agitate the contents of container 17 and thoroughly mix the washsolution and blood cells.

The wash solution is then separated from the blood cells and transferredto compartment 24 of container 16 in the same manner as has beendescribed for the preservative liquid. The washing step described aboveis repeated as many times as necessary and when the treatment iscompleted, container 17 contains a concentrate of washed blood cellswhile container 16 contains liquid preservative and used wash solutionin compartment 24. Compartment 23 may be empty or contain a residue ofwash solution.

It will be appreciated that the described twocompartment container withits integral conduits offer significant advantages from a manufacturingas well as from a handling point of view.

What is claimed is:

1. A container for use in treatment of liquid, particularly incentrifugal separation of liquid into fractions of different densities,comprising walls of flexible sheet material, the walls defining betweenthem a closed annular compartment for holding a discrete quantity ofliquid, said walls further defining a central area located radiallyinwardly of the inner edge of the compartment, said central area beingfixed with respect to the compartment, the walls forming said centralarea further defining a collapsible conduit through which liquid may beconveyed into or out of the container compartment, said conduit beingintegrally connected with central area and hence also with the containerwalls so as to be fixed relative to the walls, one end of the conduitconnected to the interior of the compartment, the conduit extending fromsaid one end within the central area to a further open end also withinthe central area for communication with a further fluid transportingmeans the fixed section of the conduit thus being disposed and arrangedto serve as the liquid conveying member of peristaltic pump.

2. A container as set forth in claim 1 in which the conduit is definedby heat seals joining the walls.

3. A container as set forth in claim 1 in which a connecting tube isattached to one of the walls and commu nicates with the conduit.

4. A container as set forth in claim 1 in which thewalls are generallycircular and include an upper wall, a central wall and a lower wall, theupper and central walls defining between them a first generally annular6 compartment and a first conduit communicating at one end thereof withthe first compartment and at the other end with a connecting tubesecured to the upper wall,

the central and lower walls defining between them a second generallyannular compartment and a second conduit communicating at one endthereof with the second compartment and at the other end with theconnecting tube, portions of the first and second conduits extendingalong portions of respective ones oftwo concentric circles andbeingadapted to cooperate with respective ones of two concentric rotors of aperistaltic 'pump to pass liquid into and out of the compartments.

5. A container as set forth in claim 1 in which the conduit extendsalong a portion of a circular path.

6. A container for use in treatment of liquid, particularly incentrifugal separation of liquid into fractions of different densities,comprising walls of flexible sheet material, the walls defining betweenthem a closed compartment for holding a discrete quantity of liquid anda collapsible conduit through which liquid may be conveyed into or outof the container compartment, at least a section of the conduit beingintegrally connected with the container wall so as to be fixed relativeto the walls and such that the fixed section of the conduit is disposedand arranged to serve as the liquid conveying member of a peristalticpump, said walls being generally circular and including an upper wall, acen tral wall and a lower wall, the upper and central walls definingbetween them a first generally annular compartment and a first conduitcommunicating at one end thereof with the first compartment and at theother end thereof with a connecting tube secured to the upper wall, thecentral and lower walls defining between them a second generally annularcompartment and a second conduit communicating at one end thereof withthe second compartment and at the other end with the connecting tube,portions of the first and second conduits extending along portions ofrespective ones of two concentric circles and being adapted to cooperatewith respective ones of two concentric rotors of a peristaltic pump topass liquid into and out of the compartments.

1. A container for use in treatment of liquid, particularly incentrifugal separation of liquid into fractions of different densities,comprising walls of flexible sheet material, the walls defining betweenthem a closed annular compartment for holding a discrete quantity ofliquid, said walls further defining a central area located radiallyinwardly of the inner edge of the compartment, said central area beingfixed with respect to the compartment, the walls forming said centralarea further defining a collapsible conduit through which liquid may beconveyed into or out of the container compartment, said conduit beingintegrally connected with central area and hence also with the containerwalls so as to be fixed relative to the walls, one end of the conduitconnected to the interior of the compartment, the conduit extending fromsaid one end within the central area to a further open end also withinthe central area for communication with a further fluid transportingmeans the fixed section of the conduit thus being disposed and arrangedto serve as the liquid conveying member of peristaltic pump.
 2. Acontainer as set forth in claim 1 in which the conduit is defined byheat seals joining the walls.
 3. A container as set forth in claim 1 inwhich a connecting tube is attached to one of the walls and communicateswith the conduit.
 4. A container as set forth in claim 1 in which thewalls are generally circular and include an upper wall, a central walland a lower wall, the upper and central walls defining between them afirst generally annular compartment and a first conduit communicating atone end thereof with the first compartment and at the other end with aconnecting tube secured to the upper wall, the central and lower wallsdefining between them a second generally annular compartment and asecond conduit communicating at one end thereof with the secondcompartment and at the other end with the connecting tube, portions ofthe first and second conduits extending along portions of respectiveones of two concentric circles and being adapted to cooperate withrespective ones of two concentric rotors of a peristaltic pump to passliquid into and out of the compartments.
 5. A container as set forth inclaim 1 in which the conduit extends along a portion of a circular path.6. A container for use in treatment of liquid, particularly incentrifugal separation of liquid into fractions of different densities,comprising walls of flexible sheet material, the walls defining betweenthem a closed compartment for holding a discrete quantity of liquid anda collapsible conduit through which liquid may be conveyed into or outof the container compartment, at least a section of the conduit beingintegrally connected with the container wall so as to be fixed relativeto the walls and such that the fixed section of the conduit is disposedand arranged to serve as the liquid conveying member of a peristalticpump, said walls being generally circular and including an upper wall, acentral wall and a lower wall, the upper and central walls definingbetween them a first generally annular compartment and a first conduitcommunicating at one end thereof with the first compartment and at theother end thereof with a connecting tube secured to the upper wall, thecentral and lower walls defining between them a second generally annularcompartment and a second conduit communicating at one end thereof withthe second compartment and at the other end with the connecting tube,portions of the first and second conduits extending along portions ofrespective ones of two concentric circles and being adapted to cooperatewith respective ones of two concentric rotors of a peristaltic pump topass liquid into and out of the compartments.